Slideshow: 10 most popular national parks

Americans made millions of visits to national parks in 2012. The top ten most-popular destinations had more than 30 million visitors. Here is the recently released list of the ten most popular national parks in American.

Americans made millions of visits to national parks in 2012. The top ten most-popular destinations had more than 30 million visitors. Here is the recently released list of the ten most popular national parks in American.